1. Field of the Invention
The present invention relates to integrated optical components and, in particular, to optical components that are readily coupled to optical fibers and to optical components capable of switching an optical path on and off.
2. Description of the Related Art
Optical networks have become prevalent in long distance communication networks, including for the backbone of the Internet. Demand for additional bandwidth in all manner of optical networks continues to grow and a variety of different strategies have been adopted to improve the utilization of the bandwidth within existing optical fiber networks. There is, for example, increasing utilization of multiple wavelength or broad-spectrum light communication over optical fiber links, generally using the technology known as wavelength division multiplexing (xe2x80x9cWDMxe2x80x9d). Presently the most common implementation of WDM communication uses a plurality of different lasers as light sources, with each laser emitting light at a wavelength different from the wavelengths emitted by the other lasers in the system. Each of the different wavelengths of light represents a different, substantially independent communication channel and symbols can be transmitted on each of these different communication channels using a modulation and encoding stream appropriate to the channel. For example, each of the channels might be modulated and encoded using time domain techniques.
Optical networks require a variety of switches to be operable, including add drop switches and multiplexers. The lack of adequate, reliable and cost-effective switches has retarded the implementation of optical networks and has limited switched optical networks to very high traffic systems.
Micro-mechanical systems include devices such as gyroscopes and mirror arrays formed on the surface of semiconductor substrates. In essence, these are very small mechanical devices formed on the surface of semiconductor substrates using semiconductor fabrication technology, including photolithography, thin film deposition, etching, and impurity doping by diffusion and ion-implantation. Micro-mechanical systems often include moving parts that are released from the underlying substrate and can move independently of the substrate.
Aspects of the present invention take advantage of micro-mechanical manufacturing technology to provide optical components.
One aspect of the invention provides an optical system that includes an optical component formed on a substrate and an alignment channel formed on the substrate. The alignment channel is adapted to accept an optical fiber and couple the optical fiber to the optical component. The alignment channel includes first and second edges extending along a length of an optical fiber positioned within the alignment channel and positioned within the alignment channel so that an optical fiber positioned within the alignment channel is supported and positioned by the first and second edges.
Another aspect of the present invention provides an optical system having a substrate with an optical path defined therein. The substrate includes a shutter translatable with respect to the optical path, the shutter within the optical path in at least one position and the shutter not in the optical path in at least one position, the shutter translatable in response to electrical signals. The substrate further includes first and second alignment channels, with the first alignment channel holding a first optical fiber and positioning a first core of the first optical fiber with respect to the second alignment channel. The second alignment channel holds a second optical fiber and positions a second core of the second optical fiber with respect to the first alignment channel. The optical path passes through the first and second alignment channels and a portion of the optical path extends outside of the first and second alignment channels with the shutter selectively positioned within the portion of the optical path outside of the first and second alignment channels. The first and second alignment channels are offset with respect to one another so that the first core and the second core are misaligned when the first and second fibers are positioned within the alignment channels.
Still another aspect of the present invention provides an optical system having an optical path defined in part by first and second optical fibers, a portion of the optical path extending outside of the first and second optical fibers. A substrate at least partially includes the optical path. The substrate further includes a shutter selectively translatable with respect to the optical path so that the shutter is within the optical path in at least one position and the shutter is not in the optical path in at least one position. The shutter is selectively translatable in response to electrical signals within the portion of the optical path outside of the first and second optical fibers. A latch is formed in the substrate and is adapted to couple to a portion of the shutter and hold the shutter out of the portion of the optical path outside of the first and second optical fibers.
Yet another aspect of the present invention provides an optical system, comprising a substrate having an optical path defined therein. The substrate further includes a shutter translatable with respect to the optical path, the shutter within the optical path in a first position and the shutter not in the optical path in at least a second position. The shutter is translatable in response to electrical signals and the shutter has a reflecting surface positioned within the optical path when the shutter is in the first position. The substrate further includes first and second alignment channels, with the first alignment channel holding a first optical fiber and positioning a first core of the first optical fiber with respect to the second alignment channel. The second alignment channel holds a second optical fiber and positions a second core of the second optical fiber with respect to the first alignment channel. The optical path passes through the first and second fibers and a portion of the optical path extends outside of the first and second fibers with the shutter selectively positioned within the portion of the optical path outside of the first and second fibers. Faces of the first and second fibers each have an angle with respect to the optical path sufficient to prevent back reflections from the shutter when the shutter is in the first position.